The present invention deals with thermostats, and more particularly to solid state thermostats with low EMI/EMC noise operation.
Mechanical thermostats are oftentimes used to control temperature in various different control environments. There are, however, various drawbacks associated with such conventional type thermostats. For example, mechanical thermostats tend to produce noise in the form of electromagnetic interference (EMI). This can be significant in environments in which noise level is critical. Furthermore, cycling on/off of such thermostats results in wear which can eventually lead to reliability problems.
Electronic thermostats have been developed which may alleviate some of the disadvantages associated with conventional mechanical thermostats. However, there remains a strong need in the art for a solid-state thermostat which provides low noise operation and high reliability.
According to one aspect of the invention, a low noise solid state thermostat is provided. The thermostat includes a thermostat input operatively configured to be coupled to a temperature sensor; a comparator for comparing an output of the temperature sensor to a predetermined set-point temperature; and solid-state switching circuitry operatively coupled to the comparator for selectively switching current to a thermostat output based on an output of the comparator.
The following description and the annexed drawings set forth in detail certain illustrative embodiments of the invention. These embodiments are indicative, however, of but a few of the various ways in which the principles of the invention may be employed. Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the drawings.